For a 250cc 2 stroke engine that only has boyesen reed and exhaust (no porting) what would be a better carb to get a 36mm or a 38mm. Currently my trike has the stock 32mm Mikuni. What do you guys think?

 

A 36 would probably be better for you now but if you plan on doing other modifications you can go with the 38. Or you could save money and jet the stock one. Your call.

 

When you say rejet. Do you mean change the main jet of the carb?

 

The main jet, pilot jet, needle clip position, etc. Whatever it needs. It would probably be just the main jet and maybe the pilot jet. If you have fmf pipes you can call their technical support line and they will tell you what you need.

 

If I were you I would get 36mm.

 

try a keihin 34mm they came stock on 250r's . people upgrade so you can probably get one real cheap. i saw a whole box of used ones at a cycle shop.

 

Is a Mikuni TMS38mm any good for my trike? I guess it should be better than the OEM round slide 32mm. What do you think?

 

a little big. Maybe if your ported.

 

I had a 38mm tmx mikuni which had excellent response. IMO a 38mm has excellent response and really lets the bike pull hard in 3rd gear or higher.

 

i wouls stick with a 36 mm carb. now would youm want a pj (all around carb) or pwk (in your face throttle response and max power). the pwk is used by most people for getting the most power and throttle response out of there quad. if your trail riding i would go with the pj. it has smoother power dilivery and usually a little more usable torgue. if your plan on porting in the future. i'd go with the 38 mm pwk airstyker carb. just my opinion. fellow racer airtime